Viral diseases afflict man, plants, insects, and animals. The prevention and control of viral diseases have important health and economic implications.
Viral diseases contribute to afflictions in humans including common colds, herpes, and cancer, and the importance of their control is obvious. It is important to control viral diseases in animals for economic reasons and because animals, including insects can become virus reservoirs or carriers which facilitate the spreading of viral diseases to humans. Further, viral plant diseases have been known to disrupt the growth of commercial plant crops, including fruit trees, tobacco, and various vegetables.
The prevention and control of viral diseases are thus of prime importance to man, and considerable research has been devoted to antiviral measures. Certain methods and chemical compositions have been developed which aid in inhibiting, controlling or destroying viruses, but additional methods and antiviral chemical compositions are needed.
A potential source for antiviral compositions is plant and animal life and of particular interest herein is the firefly.
Previous work reported by Meinwald et al. and Goetz, et al. has indicated that Photinus can be a source of lucibufagin compounds. Such work has been reported in the following references. Meinwald et al., J. Am. Chem. Soc., 101: 11, (1979) Pp. 3055-3060, (discloses esters of 12-oxo-2,5,11-trihydroxybufalin derived from the firefly Photinus, see compounds 5, 6, 11 and 12); Goetz et al. Experientia, 37, (1981), Pp. 679-680 (discloses esters of 12-oxo-2,5,11-trihydroxybufalin derived from the firefly Photinus pyralis, see compounds 1-6); Eisner et al, Proc. Natl. Acad. Sci. USA, Vol. 75, No. 2, (1978), pp. 905-908 (discloses lucibufagins derived from firefly Photinus ignitus and P. marginellus); and Goetz et al., Helv. Chim. Acta, 62, Fasc. 5, Nr. 144 (1979), pp. 1396-1400 (discloses lucibufagins from fireflies Photinus ignitus and P. marginellus, see compounds 4 and 9). No antiviral activity was reported for any of the above-identified compounds. The entire disclosures of all of the above-noted literature references are hereby incorporated herein by reference.
It has been found by the present inventors that certain lucibufagin compounds, derived from fireflies, have antiviral activity.